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b=kAjw7zJu6exQmrGC2lB1KRNaAMyyXdP5zNcwwsxzJN3yYvdjwq2FQPEGrwoGc/uQ9 EEoYiJT6sfuDPBk9VFp23uX7QZSc5r/PJQdHmzNH+2rc0ZHooSkpNqCngF4SLCdJtY ORAGz3f0eo12Gy+YG5MyyeyOiGS31NAvx1g97a5fvhtAytRAtMzvLPEk3xLNlxKemq yEmvF6eNsopNkIsuo+EIREPNBC/n1Z7/lNVlkGCreiXSCLC8OtQoqS9oyyRpdlOS/8 4+GXN3PvOjEIpycgoZO8M2neVs2cc68J8FZBIEz6Tg8+VzHDpxOx/5JkHxnMQnrUGY JAQpxBe2spC+Q== Message-ID: <44a20360-c791-491d-bd84-e161b7c6a9f0@kernel.org> Date: Wed, 5 Aug 2026 00:01:22 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC v2 PATCH 0/16] Optimize this_cpu_*() ops for non-x86 (ARM64 for this series) To: "Christoph Lameter (Ampere)" Cc: "Lorenzo Stoakes (ARM)" , Linus Torvalds , Mark Rutland , Yang Shi , Ryan Roberts , dennis@kernel.org, tj@kernel.org, urezki@gmail.com, catalin.marinas@arm.com, will@kernel.org, akpm@linux-foundation.org, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Jason Gunthorpe References: <0344c559-1959-4531-9265-d5a5180eb7cd@arm.com> <25d1e09b-53e4-7cd5-87db-b58437e4e690@gentwo.org> <4887267b-dc26-4c33-96ca-8dff054a0d1f@kernel.org> <8d6119c7-2216-fcdd-d0b9-cc60ccc8caf3@gentwo.org> <4baf6edb-c84b-4da9-b905-4d40d4bf5fdc@kernel.org> <7f2b2030-b912-70ee-5019-02dad2e87ca6@gentwo.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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Look at Yang's posts. > I'm getting tired of this. So to be clear: claiming that the additional instructions are unacceptable I'd expect something minimal like: "removing these 3 instructions speeds up micro-benchmark (a, b, c) by X% and macro-benchmarks (d, e, f) by Y% compared to Mark's approach". [1] https://lore.kernel.org/r/ea268481-d584-4744-99d6-0b05aade7d5d@kernel.org -- Cheers, David